Class LinkedHashSet<T>

  • Type Parameters:
    T - Component type
    All Implemented Interfaces:
    Foldable<T>, Set<T>, Traversable<T>, Function1<T,​java.lang.Boolean>, Iterable<T>, Value<T>, java.io.Serializable, java.lang.Iterable<T>, java.util.function.Function<T,​java.lang.Boolean>

    public final class LinkedHashSet<T>
    extends java.lang.Object
    implements Set<T>, java.io.Serializable
    An immutable HashSet implementation that has predictable (insertion-order) iteration.
    See Also:
    Serialized Form
    • Method Detail

      • collector

        public static <T> java.util.stream.Collector<T,​java.util.ArrayList<T>,​LinkedHashSet<T>> collector()
        Returns a Collector which may be used in conjunction with Stream.collect(Collector) to obtain a LinkedHashSet.
        Type Parameters:
        T - Component type of the LinkedHashSet.
        Returns:
        A io.vavr.collection.LinkedHashSet Collector.
      • narrow

        public static <T> LinkedHashSet<T> narrow​(LinkedHashSet<? extends T> linkedHashSet)
        Narrows a widened LinkedHashSet<? extends T> to LinkedHashSet<T> by performing a type-safe cast. This is eligible because immutable/read-only collections are covariant.
        Type Parameters:
        T - Component type of the linkedHashSet.
        Parameters:
        linkedHashSet - A LinkedHashSet.
        Returns:
        the given linkedHashSet instance as narrowed type LinkedHashSet<T>.
      • of

        public static <T> LinkedHashSet<T> of​(T element)
        Returns a singleton LinkedHashSet, i.e. a LinkedHashSet of one element.
        Type Parameters:
        T - The component type
        Parameters:
        element - An element.
        Returns:
        A new LinkedHashSet instance containing the given element
      • of

        @SafeVarargs
        public static <T> LinkedHashSet<T> of​(T... elements)
        Creates a LinkedHashSet of the given elements.
        LinkedHashSet.of(1, 2, 3, 4)
        Type Parameters:
        T - Component type of the LinkedHashSet.
        Parameters:
        elements - Zero or more elements.
        Returns:
        A set containing the given elements.
        Throws:
        java.lang.NullPointerException - if elements is null
      • tabulate

        public static <T> LinkedHashSet<T> tabulate​(int n,
                                                    java.util.function.Function<? super java.lang.Integer,​? extends T> f)
        Returns a LinkedHashSet containing n values of a given Function f over a range of integer values from 0 to n - 1.
        Type Parameters:
        T - Component type of the LinkedHashSet
        Parameters:
        n - The number of elements in the LinkedHashSet
        f - The Function computing element values
        Returns:
        A LinkedHashSet consisting of elements f(0),f(1), ..., f(n - 1)
        Throws:
        java.lang.NullPointerException - if f is null
      • fill

        public static <T> LinkedHashSet<T> fill​(int n,
                                                java.util.function.Supplier<? extends T> s)
        Returns a LinkedHashSet containing tuples returned by n calls to a given Supplier s.
        Type Parameters:
        T - Component type of the LinkedHashSet
        Parameters:
        n - The number of elements in the LinkedHashSet
        s - The Supplier computing element values
        Returns:
        A LinkedHashSet of size n, where each element contains the result supplied by s.
        Throws:
        java.lang.NullPointerException - if s is null
      • ofAll

        public static <T> LinkedHashSet<T> ofAll​(java.lang.Iterable<? extends T> elements)
        Creates a LinkedHashSet of the given elements.
        Type Parameters:
        T - The value type
        Parameters:
        elements - Set elements
        Returns:
        A new LinkedHashSet containing the given entries
      • ofAll

        public static <T> LinkedHashSet<T> ofAll​(java.util.stream.Stream<? extends T> javaStream)
        Creates a LinkedHashSet that contains the elements of the given Stream.
        Type Parameters:
        T - Component type of the Stream.
        Parameters:
        javaStream - A Stream
        Returns:
        A LinkedHashSet containing the given elements in the same order.
      • ofAll

        public static LinkedHashSet<java.lang.Boolean> ofAll​(boolean... elements)
        Creates a LinkedHashSet from boolean values.
        Parameters:
        elements - boolean values
        Returns:
        A new LinkedHashSet of Boolean values
        Throws:
        java.lang.NullPointerException - if elements is null
      • ofAll

        public static LinkedHashSet<java.lang.Byte> ofAll​(byte... elements)
        Creates a LinkedHashSet from byte values.
        Parameters:
        elements - byte values
        Returns:
        A new LinkedHashSet of Byte values
        Throws:
        java.lang.NullPointerException - if elements is null
      • ofAll

        public static LinkedHashSet<java.lang.Character> ofAll​(char... elements)
        Creates a LinkedHashSet from char values.
        Parameters:
        elements - char values
        Returns:
        A new LinkedHashSet of Character values
        Throws:
        java.lang.NullPointerException - if elements is null
      • ofAll

        public static LinkedHashSet<java.lang.Double> ofAll​(double... elements)
        Creates a LinkedHashSet from double values.
        Parameters:
        elements - double values
        Returns:
        A new LinkedHashSet of Double values
        Throws:
        java.lang.NullPointerException - if elements is null
      • ofAll

        public static LinkedHashSet<java.lang.Float> ofAll​(float... elements)
        Creates a LinkedHashSet from float values.
        Parameters:
        elements - a float values
        Returns:
        A new LinkedHashSet of Float values
        Throws:
        java.lang.NullPointerException - if elements is null
      • ofAll

        public static LinkedHashSet<java.lang.Integer> ofAll​(int... elements)
        Creates a LinkedHashSet from int values.
        Parameters:
        elements - int values
        Returns:
        A new LinkedHashSet of Integer values
        Throws:
        java.lang.NullPointerException - if elements is null
      • ofAll

        public static LinkedHashSet<java.lang.Long> ofAll​(long... elements)
        Creates a LinkedHashSet from long values.
        Parameters:
        elements - long values
        Returns:
        A new LinkedHashSet of Long values
        Throws:
        java.lang.NullPointerException - if elements is null
      • ofAll

        public static LinkedHashSet<java.lang.Short> ofAll​(short... elements)
        Creates a LinkedHashSet from short values.
        Parameters:
        elements - short values
        Returns:
        A new LinkedHashSet of Short values
        Throws:
        java.lang.NullPointerException - if elements is null
      • range

        public static LinkedHashSet<java.lang.Integer> range​(int from,
                                                             int toExclusive)
        Creates a LinkedHashSet of int numbers starting from from, extending to toExclusive - 1.

        Examples:

         
         LinkedHashSet.range(0, 0)  // = LinkedHashSet()
         LinkedHashSet.range(2, 0)  // = LinkedHashSet()
         LinkedHashSet.range(-2, 2) // = LinkedHashSet(-2, -1, 0, 1)
         
         
        Parameters:
        from - the first number
        toExclusive - the last number + 1
        Returns:
        a range of int values as specified or the empty range if from >= toExclusive
      • range

        public static LinkedHashSet<java.lang.Character> range​(char from,
                                                               char toExclusive)
      • rangeBy

        public static LinkedHashSet<java.lang.Integer> rangeBy​(int from,
                                                               int toExclusive,
                                                               int step)
        Creates a LinkedHashSet of int numbers starting from from, extending to toExclusive - 1, with step.

        Examples:

         
         LinkedHashSet.rangeBy(1, 3, 1)  // = LinkedHashSet(1, 2)
         LinkedHashSet.rangeBy(1, 4, 2)  // = LinkedHashSet(1, 3)
         LinkedHashSet.rangeBy(4, 1, -2) // = LinkedHashSet(4, 2)
         LinkedHashSet.rangeBy(4, 1, 2)  // = LinkedHashSet()
         
         
        Parameters:
        from - the first number
        toExclusive - the last number + 1
        step - the step
        Returns:
        a range of long values as specified or the empty range if
        from >= toInclusive and step > 0 or
        from <= toInclusive and step < 0
        Throws:
        java.lang.IllegalArgumentException - if step is zero
      • rangeBy

        public static LinkedHashSet<java.lang.Character> rangeBy​(char from,
                                                                 char toExclusive,
                                                                 int step)
      • rangeBy

        @GwtIncompatible
        public static LinkedHashSet<java.lang.Double> rangeBy​(double from,
                                                              double toExclusive,
                                                              double step)
      • range

        public static LinkedHashSet<java.lang.Long> range​(long from,
                                                          long toExclusive)
        Creates a LinkedHashSet of long numbers starting from from, extending to toExclusive - 1.

        Examples:

         
         LinkedHashSet.range(0L, 0L)  // = LinkedHashSet()
         LinkedHashSet.range(2L, 0L)  // = LinkedHashSet()
         LinkedHashSet.range(-2L, 2L) // = LinkedHashSet(-2L, -1L, 0L, 1L)
         
         
        Parameters:
        from - the first number
        toExclusive - the last number + 1
        Returns:
        a range of long values as specified or the empty range if from >= toExclusive
      • rangeBy

        public static LinkedHashSet<java.lang.Long> rangeBy​(long from,
                                                            long toExclusive,
                                                            long step)
        Creates a LinkedHashSet of long numbers starting from from, extending to toExclusive - 1, with step.

        Examples:

         
         LinkedHashSet.rangeBy(1L, 3L, 1L)  // = LinkedHashSet(1L, 2L)
         LinkedHashSet.rangeBy(1L, 4L, 2L)  // = LinkedHashSet(1L, 3L)
         LinkedHashSet.rangeBy(4L, 1L, -2L) // = LinkedHashSet(4L, 2L)
         LinkedHashSet.rangeBy(4L, 1L, 2L)  // = LinkedHashSet()
         
         
        Parameters:
        from - the first number
        toExclusive - the last number + 1
        step - the step
        Returns:
        a range of long values as specified or the empty range if
        from >= toInclusive and step > 0 or
        from <= toInclusive and step < 0
        Throws:
        java.lang.IllegalArgumentException - if step is zero
      • rangeClosed

        public static LinkedHashSet<java.lang.Integer> rangeClosed​(int from,
                                                                   int toInclusive)
        Creates a LinkedHashSet of int numbers starting from from, extending to toInclusive.

        Examples:

         
         LinkedHashSet.rangeClosed(0, 0)  // = LinkedHashSet(0)
         LinkedHashSet.rangeClosed(2, 0)  // = LinkedHashSet()
         LinkedHashSet.rangeClosed(-2, 2) // = LinkedHashSet(-2, -1, 0, 1, 2)
         
         
        Parameters:
        from - the first number
        toInclusive - the last number
        Returns:
        a range of int values as specified or the empty range if from > toInclusive
      • rangeClosed

        public static LinkedHashSet<java.lang.Character> rangeClosed​(char from,
                                                                     char toInclusive)
      • rangeClosedBy

        public static LinkedHashSet<java.lang.Integer> rangeClosedBy​(int from,
                                                                     int toInclusive,
                                                                     int step)
        Creates a LinkedHashSet of int numbers starting from from, extending to toInclusive, with step.

        Examples:

         
         LinkedHashSet.rangeClosedBy(1, 3, 1)  // = LinkedHashSet(1, 2, 3)
         LinkedHashSet.rangeClosedBy(1, 4, 2)  // = LinkedHashSet(1, 3)
         LinkedHashSet.rangeClosedBy(4, 1, -2) // = LinkedHashSet(4, 2)
         LinkedHashSet.rangeClosedBy(4, 1, 2)  // = LinkedHashSet()
         
         
        Parameters:
        from - the first number
        toInclusive - the last number
        step - the step
        Returns:
        a range of int values as specified or the empty range if
        from > toInclusive and step > 0 or
        from < toInclusive and step < 0
        Throws:
        java.lang.IllegalArgumentException - if step is zero
      • rangeClosedBy

        public static LinkedHashSet<java.lang.Character> rangeClosedBy​(char from,
                                                                       char toInclusive,
                                                                       int step)
      • rangeClosedBy

        @GwtIncompatible
        public static LinkedHashSet<java.lang.Double> rangeClosedBy​(double from,
                                                                    double toInclusive,
                                                                    double step)
      • rangeClosed

        public static LinkedHashSet<java.lang.Long> rangeClosed​(long from,
                                                                long toInclusive)
        Creates a LinkedHashSet of long numbers starting from from, extending to toInclusive.

        Examples:

         
         LinkedHashSet.rangeClosed(0L, 0L)  // = LinkedHashSet(0L)
         LinkedHashSet.rangeClosed(2L, 0L)  // = LinkedHashSet()
         LinkedHashSet.rangeClosed(-2L, 2L) // = LinkedHashSet(-2L, -1L, 0L, 1L, 2L)
         
         
        Parameters:
        from - the first number
        toInclusive - the last number
        Returns:
        a range of long values as specified or the empty range if from > toInclusive
      • rangeClosedBy

        public static LinkedHashSet<java.lang.Long> rangeClosedBy​(long from,
                                                                  long toInclusive,
                                                                  long step)
        Creates a LinkedHashSet of long numbers starting from from, extending to toInclusive, with step.

        Examples:

         
         LinkedHashSet.rangeClosedBy(1L, 3L, 1L)  // = LinkedHashSet(1L, 2L, 3L)
         LinkedHashSet.rangeClosedBy(1L, 4L, 2L)  // = LinkedHashSet(1L, 3L)
         LinkedHashSet.rangeClosedBy(4L, 1L, -2L) // = LinkedHashSet(4L, 2L)
         LinkedHashSet.rangeClosedBy(4L, 1L, 2L)  // = LinkedHashSet()
         
         
        Parameters:
        from - the first number
        toInclusive - the last number
        step - the step
        Returns:
        a range of int values as specified or the empty range if
        from > toInclusive and step > 0 or
        from < toInclusive and step < 0
        Throws:
        java.lang.IllegalArgumentException - if step is zero
      • add

        public LinkedHashSet<T> add​(T element)
        Add the given element to this set, replacing existing one if it is already contained.

        Note that this method has a worst-case linear complexity.

        Specified by:
        add in interface Set<T>
        Parameters:
        element - The element to be added.
        Returns:
        A new set containing all elements of this set and also element.
      • addAll

        public LinkedHashSet<T> addAll​(java.lang.Iterable<? extends T> elements)
        Adds all of the given elements to this set, replacing existing one if they are not already contained.

        Note that this method has a worst-case quadratic complexity.

        Specified by:
        addAll in interface Set<T>
        Parameters:
        elements - The elements to be added.
        Returns:
        A new set containing all elements of this set and the given elements, if not already contained.
      • collect

        public <R> LinkedHashSet<R> collect​(PartialFunction<? super T,​? extends R> partialFunction)
        Description copied from interface: Traversable
        Collects all elements that are in the domain of the given partialFunction by mapping the elements to type R.

        More specifically, for each of this elements in iteration order first it is checked

        
         partialFunction.isDefinedAt(element)
         
        If the elements makes it through that filter, the mapped instance is added to the result collection
        
         R newElement = partialFunction.apply(element)
         
        Note:If this Traversable is ordered (i.e. extends Ordered, the caller of collect has to ensure that the elements are comparable (i.e. extend Comparable).
        Specified by:
        collect in interface Set<T>
        Specified by:
        collect in interface Traversable<T>
        Type Parameters:
        R - The new element type
        Parameters:
        partialFunction - A function that is not necessarily defined of all elements of this traversable.
        Returns:
        A new Traversable instance containing elements of type R
      • contains

        public boolean contains​(T element)
        Description copied from interface: Value
        Shortcut for exists(e -> Objects.equals(e, element)), tests if the given element is contained.
        Specified by:
        contains in interface Set<T>
        Specified by:
        contains in interface Value<T>
        Parameters:
        element - An Object of type A, may be null.
        Returns:
        true, if element is contained, false otherwise.
      • diff

        public LinkedHashSet<T> diff​(Set<? extends T> elements)
        Description copied from interface: Set
        Calculates the difference between this set and another set.

        See also Set.removeAll(Iterable).

        Specified by:
        diff in interface Set<T>
        Parameters:
        elements - Elements to be removed from this set.
        Returns:
        A new Set containing all elements of this set which are not located in that set.
      • distinct

        public LinkedHashSet<T> distinct()
        Description copied from interface: Traversable
        Returns a new version of this which contains no duplicates. Elements are compared using equals.
        Specified by:
        distinct in interface Set<T>
        Specified by:
        distinct in interface Traversable<T>
        Returns:
        a new Traversable containing this elements without duplicates
      • distinctBy

        public LinkedHashSet<T> distinctBy​(java.util.Comparator<? super T> comparator)
        Description copied from interface: Traversable
        Returns a new version of this which contains no duplicates. Elements are compared using the given comparator.
        Specified by:
        distinctBy in interface Set<T>
        Specified by:
        distinctBy in interface Traversable<T>
        Parameters:
        comparator - A comparator
        Returns:
        a new Traversable containing this elements without duplicates
      • distinctBy

        public <U> LinkedHashSet<T> distinctBy​(java.util.function.Function<? super T,​? extends U> keyExtractor)
        Description copied from interface: Traversable
        Returns a new version of this which contains no duplicates. Elements mapped to keys which are compared using equals.

        The elements of the result are determined in the order of their occurrence - first match wins.

        Specified by:
        distinctBy in interface Set<T>
        Specified by:
        distinctBy in interface Traversable<T>
        Type Parameters:
        U - key type
        Parameters:
        keyExtractor - A key extractor
        Returns:
        a new Traversable containing this elements without duplicates
      • drop

        public LinkedHashSet<T> drop​(int n)
        Description copied from interface: Traversable
        Drops the first n elements of this or all elements, if this length < n.
        Specified by:
        drop in interface Set<T>
        Specified by:
        drop in interface Traversable<T>
        Parameters:
        n - The number of elements to drop.
        Returns:
        a new instance consisting of all elements of this except the first n ones, or else the empty instance, if this has less than n elements.
      • dropRight

        public LinkedHashSet<T> dropRight​(int n)
        Description copied from interface: Traversable
        Drops the last n elements of this or all elements, if this length < n.
        Specified by:
        dropRight in interface Set<T>
        Specified by:
        dropRight in interface Traversable<T>
        Parameters:
        n - The number of elements to drop.
        Returns:
        a new instance consisting of all elements of this except the last n ones, or else the empty instance, if this has less than n elements.
      • dropUntil

        public LinkedHashSet<T> dropUntil​(java.util.function.Predicate<? super T> predicate)
        Description copied from interface: Traversable
        Drops elements until the predicate holds for the current element.
        Specified by:
        dropUntil in interface Set<T>
        Specified by:
        dropUntil in interface Traversable<T>
        Parameters:
        predicate - A condition tested subsequently for this elements.
        Returns:
        a new instance consisting of all elements starting from the first one which does satisfy the given predicate.
      • dropWhile

        public LinkedHashSet<T> dropWhile​(java.util.function.Predicate<? super T> predicate)
        Description copied from interface: Traversable
        Drops elements while the predicate holds for the current element.

        Note: This is essentially the same as dropUntil(predicate.negate()). It is intended to be used with method references, which cannot be negated directly.

        Specified by:
        dropWhile in interface Set<T>
        Specified by:
        dropWhile in interface Traversable<T>
        Parameters:
        predicate - A condition tested subsequently for this elements.
        Returns:
        a new instance consisting of all elements starting from the first one which does not satisfy the given predicate.
      • filter

        public LinkedHashSet<T> filter​(java.util.function.Predicate<? super T> predicate)
        Description copied from interface: Traversable
        Returns a new traversable consisting of all elements which satisfy the given predicate.
        Specified by:
        filter in interface Set<T>
        Specified by:
        filter in interface Traversable<T>
        Parameters:
        predicate - A predicate
        Returns:
        a new traversable
      • filterNot

        public LinkedHashSet<T> filterNot​(java.util.function.Predicate<? super T> predicate)
        Description copied from interface: Traversable
        Returns a new traversable consisting of all elements which do not satisfy the given predicate.

        The default implementation is equivalent to

        filter(predicate.negate()
        Specified by:
        filterNot in interface Set<T>
        Specified by:
        filterNot in interface Traversable<T>
        Parameters:
        predicate - A predicate
        Returns:
        a new traversable
      • reject

        @Deprecated
        public LinkedHashSet<T> reject​(java.util.function.Predicate<? super T> predicate)
        Deprecated.
        Description copied from interface: Traversable
        Returns a new traversable consisting of all elements which do not satisfy the given predicate.

        The default implementation is equivalent to

        filter(predicate.negate()
        Specified by:
        reject in interface Set<T>
        Specified by:
        reject in interface Traversable<T>
        Parameters:
        predicate - A predicate
        Returns:
        a new traversable
      • flatMap

        public <U> LinkedHashSet<U> flatMap​(java.util.function.Function<? super T,​? extends java.lang.Iterable<? extends U>> mapper)
        Description copied from interface: Traversable
        FlatMaps this Traversable.
        Specified by:
        flatMap in interface Set<T>
        Specified by:
        flatMap in interface Traversable<T>
        Type Parameters:
        U - The resulting component type.
        Parameters:
        mapper - A mapper
        Returns:
        A new Traversable instance.
      • foldRight

        public <U> U foldRight​(U zero,
                               java.util.function.BiFunction<? super T,​? super U,​? extends U> f)
        Description copied from interface: Traversable
        Folds this elements from the right, starting with zero and successively calling combine.

        Example:

         
         // = "!cba"
         List("a", "b", "c").foldRight("!", (x, xs) -> xs + x)
          
        Specified by:
        foldRight in interface Foldable<T>
        Specified by:
        foldRight in interface Traversable<T>
        Type Parameters:
        U - the type of the folded value
        Parameters:
        zero - A zero element to start with.
        f - A function which combines elements.
        Returns:
        a folded value
      • groupBy

        public <C> Map<C,​LinkedHashSet<T>> groupBy​(java.util.function.Function<? super T,​? extends C> classifier)
        Description copied from interface: Traversable
        Groups this elements by classifying the elements.
        Specified by:
        groupBy in interface Set<T>
        Specified by:
        groupBy in interface Traversable<T>
        Type Parameters:
        C - classified class type
        Parameters:
        classifier - A function which classifies elements into classes
        Returns:
        A Map containing the grouped elements
        See Also:
        Traversable.arrangeBy(Function)
      • grouped

        public Iterator<LinkedHashSet<T>> grouped​(int size)
        Description copied from interface: Traversable
        Groups this Traversable into fixed size blocks.

        Let length be the length of this Iterable. Then grouped is defined as follows:

        • If this.isEmpty(), the resulting Iterator is empty.
        • If size <= length, the resulting Iterator will contain length / size blocks of size size and maybe a non-empty block of size length % size, if there are remaining elements.
        • If size > length, the resulting Iterator will contain one block of size length.
        Examples:
         
         [].grouped(1) = []
         [].grouped(0) throws
         [].grouped(-1) throws
         [1,2,3,4].grouped(2) = [[1,2],[3,4]]
         [1,2,3,4,5].grouped(2) = [[1,2],[3,4],[5]]
         [1,2,3,4].grouped(5) = [[1,2,3,4]]
         
         
        Please note that grouped(int) is a special case of Traversable.sliding(int, int), i.e. grouped(size) is the same as sliding(size, size).
        Specified by:
        grouped in interface Set<T>
        Specified by:
        grouped in interface Traversable<T>
        Parameters:
        size - a positive block size
        Returns:
        A new Iterator of grouped blocks of the given size
      • hasDefiniteSize

        public boolean hasDefiniteSize()
        Description copied from interface: Traversable
        Checks if this Traversable is known to have a finite size.

        This method should be implemented by classes only, i.e. not by interfaces.

        Specified by:
        hasDefiniteSize in interface Traversable<T>
        Returns:
        true, if this Traversable is known to have a finite size, false otherwise.
      • head

        public T head()
        Description copied from interface: Traversable
        Returns the first element of a non-empty Traversable.
        Specified by:
        head in interface Traversable<T>
        Returns:
        The first element of this Traversable.
      • headOption

        public Option<T> headOption()
        Description copied from interface: Traversable
        Returns the first element of a non-empty Traversable as Option.
        Specified by:
        headOption in interface Traversable<T>
        Returns:
        Some(element) or None if this is empty.
      • intersect

        public LinkedHashSet<T> intersect​(Set<? extends T> elements)
        Description copied from interface: Set
        Computes the intersection between this set and another set.

        See also Set.retainAll(Iterable).

        Specified by:
        intersect in interface Set<T>
        Parameters:
        elements - the set to intersect with.
        Returns:
        A new Set consisting of all elements that are both in this set and in the given set that.
      • isAsync

        public boolean isAsync()
        An LinkedHashSet's value is computed synchronously.
        Specified by:
        isAsync in interface Value<T>
        Returns:
        false
      • isEmpty

        public boolean isEmpty()
        Description copied from interface: Traversable
        Checks if this Traversable is empty.
        Specified by:
        isEmpty in interface Traversable<T>
        Specified by:
        isEmpty in interface Value<T>
        Returns:
        true, if this Traversable contains no elements, false otherwise.
      • isLazy

        public boolean isLazy()
        An LinkedHashSet's value is computed eagerly.
        Specified by:
        isLazy in interface Value<T>
        Returns:
        false
      • isTraversableAgain

        public boolean isTraversableAgain()
        Description copied from interface: Traversable
        Checks if this Traversable can be repeatedly traversed.

        This method should be implemented by classes only, i.e. not by interfaces.

        Specified by:
        isTraversableAgain in interface Traversable<T>
        Returns:
        true, if this Traversable is known to be traversable repeatedly, false otherwise.
      • isSequential

        public boolean isSequential()
        Description copied from interface: Traversable
        Checks if the elements of this Traversable appear in encounter order.
        Specified by:
        isSequential in interface Traversable<T>
        Returns:
        true, if the insertion order of elements is preserved, false otherwise.
      • iterator

        public Iterator<T> iterator()
        Description copied from interface: Traversable
        An iterator by means of head() and tail(). Subclasses may want to override this method.
        Specified by:
        iterator in interface Iterable<T>
        Specified by:
        iterator in interface java.lang.Iterable<T>
        Specified by:
        iterator in interface Set<T>
        Specified by:
        iterator in interface Traversable<T>
        Specified by:
        iterator in interface Value<T>
        Returns:
        A new Iterator of this Traversable elements.
      • length

        public int length()
        Description copied from interface: Traversable
        Computes the number of elements of this Traversable.

        Same as Traversable.size().

        Specified by:
        length in interface Set<T>
        Specified by:
        length in interface Traversable<T>
        Returns:
        the number of elements
      • map

        public <U> LinkedHashSet<U> map​(java.util.function.Function<? super T,​? extends U> mapper)
        Description copied from interface: Traversable
        Maps the elements of this Traversable to elements of a new type preserving their order, if any.
        Specified by:
        map in interface Set<T>
        Specified by:
        map in interface Traversable<T>
        Specified by:
        map in interface Value<T>
        Type Parameters:
        U - Component type of the target Traversable
        Parameters:
        mapper - A mapper.
        Returns:
        a mapped Traversable
      • mkString

        public java.lang.String mkString​(java.lang.CharSequence prefix,
                                         java.lang.CharSequence delimiter,
                                         java.lang.CharSequence suffix)
        Description copied from interface: Traversable
        Joins the string representations of this elements using a specific delimiter, prefix and suffix.

        Example: List.of("a", "b", "c").mkString("Chars(", ", ", ")") = "Chars(a, b, c)"

        Specified by:
        mkString in interface Traversable<T>
        Parameters:
        prefix - prefix of the resulting string
        delimiter - A delimiter string put between string representations of elements of this
        suffix - suffix of the resulting string
        Returns:
        a new String
      • orElse

        public LinkedHashSet<T> orElse​(java.lang.Iterable<? extends T> other)
        Description copied from interface: Traversable
        Returns this Traversable if it is nonempty, otherwise return the alternative.
        Specified by:
        orElse in interface Set<T>
        Specified by:
        orElse in interface Traversable<T>
        Parameters:
        other - An alternative Traversable
        Returns:
        this Traversable if it is nonempty, otherwise return the alternative.
      • orElse

        public LinkedHashSet<T> orElse​(java.util.function.Supplier<? extends java.lang.Iterable<? extends T>> supplier)
        Description copied from interface: Traversable
        Returns this Traversable if it is nonempty, otherwise return the result of evaluating supplier.
        Specified by:
        orElse in interface Set<T>
        Specified by:
        orElse in interface Traversable<T>
        Parameters:
        supplier - An alternative Traversable supplier
        Returns:
        this Traversable if it is nonempty, otherwise return the result of evaluating supplier.
      • partition

        public Tuple2<LinkedHashSet<T>,​LinkedHashSet<T>> partition​(java.util.function.Predicate<? super T> predicate)
        Description copied from interface: Traversable
        Creates a partition of this Traversable by splitting this elements in two in distinct traversables according to a predicate.
        Specified by:
        partition in interface Set<T>
        Specified by:
        partition in interface Traversable<T>
        Parameters:
        predicate - A predicate which classifies an element if it is in the first or the second traversable.
        Returns:
        A disjoint union of two traversables. The first Traversable contains all elements that satisfy the given predicate, the second Traversable contains all elements that don't. The original order of elements is preserved.
      • peek

        public LinkedHashSet<T> peek​(java.util.function.Consumer<? super T> action)
        Description copied from interface: Value
        Performs the given action on the first element if this is an eager implementation. Performs the given action on all elements (the first immediately, successive deferred), if this is a lazy implementation.
        Specified by:
        peek in interface Set<T>
        Specified by:
        peek in interface Traversable<T>
        Specified by:
        peek in interface Value<T>
        Parameters:
        action - The action that will be performed on the element(s).
        Returns:
        this instance
      • remove

        public LinkedHashSet<T> remove​(T element)
        Description copied from interface: Set
        Removes a specific element from this set, if present.
        Specified by:
        remove in interface Set<T>
        Parameters:
        element - The element to be removed from this set.
        Returns:
        A new set consisting of the elements of this set, without the given element.
      • removeAll

        public LinkedHashSet<T> removeAll​(java.lang.Iterable<? extends T> elements)
        Description copied from interface: Set
        Removes all of the given elements from this set, if present.
        Specified by:
        removeAll in interface Set<T>
        Parameters:
        elements - The elements to be removed from this set.
        Returns:
        A new set consisting of the elements of this set, without the given elements.
      • replace

        public LinkedHashSet<T> replace​(T currentElement,
                                        T newElement)
        Description copied from interface: Traversable
        Replaces the first occurrence (if exists) of the given currentElement with newElement.
        Specified by:
        replace in interface Set<T>
        Specified by:
        replace in interface Traversable<T>
        Parameters:
        currentElement - An element to be substituted.
        newElement - A replacement for currentElement.
        Returns:
        a Traversable containing all elements of this where the first occurrence of currentElement is replaced with newElement.
      • replaceAll

        public LinkedHashSet<T> replaceAll​(T currentElement,
                                           T newElement)
        Description copied from interface: Traversable
        Replaces all occurrences of the given currentElement with newElement.
        Specified by:
        replaceAll in interface Set<T>
        Specified by:
        replaceAll in interface Traversable<T>
        Parameters:
        currentElement - An element to be substituted.
        newElement - A replacement for currentElement.
        Returns:
        a Traversable containing all elements of this where all occurrences of currentElement are replaced with newElement.
      • retainAll

        public LinkedHashSet<T> retainAll​(java.lang.Iterable<? extends T> elements)
        Description copied from interface: Traversable
        Keeps all occurrences of the given elements from this.
        Specified by:
        retainAll in interface Set<T>
        Specified by:
        retainAll in interface Traversable<T>
        Parameters:
        elements - Elements to be kept.
        Returns:
        a Traversable containing all occurrences of the given elements.
      • scan

        public LinkedHashSet<T> scan​(T zero,
                                     java.util.function.BiFunction<? super T,​? super T,​? extends T> operation)
        Description copied from interface: Traversable
        Computes a prefix scan of the elements of the collection. Note: The neutral element z may be applied more than once.
        Specified by:
        scan in interface Set<T>
        Specified by:
        scan in interface Traversable<T>
        Parameters:
        zero - neutral element for the operator op
        operation - the associative operator for the scan
        Returns:
        a new traversable collection containing the prefix scan of the elements in this traversable collection
      • scanLeft

        public <U> LinkedHashSet<U> scanLeft​(U zero,
                                             java.util.function.BiFunction<? super U,​? super T,​? extends U> operation)
        Description copied from interface: Traversable
        Produces a collection containing cumulative results of applying the operator going left to right. Note: will not terminate for infinite-sized collections. Note: might return different results for different runs, unless the underlying collection type is ordered.
        Specified by:
        scanLeft in interface Set<T>
        Specified by:
        scanLeft in interface Traversable<T>
        Type Parameters:
        U - the type of the elements in the resulting collection
        Parameters:
        zero - the initial value
        operation - the binary operator applied to the intermediate result and the element
        Returns:
        collection with intermediate results
      • scanRight

        public <U> LinkedHashSet<U> scanRight​(U zero,
                                              java.util.function.BiFunction<? super T,​? super U,​? extends U> operation)
        Description copied from interface: Traversable
        Produces a collection containing cumulative results of applying the operator going right to left. The head of the collection is the last cumulative result. Note: will not terminate for infinite-sized collections. Note: might return different results for different runs, unless the underlying collection type is ordered.
        Specified by:
        scanRight in interface Set<T>
        Specified by:
        scanRight in interface Traversable<T>
        Type Parameters:
        U - the type of the elements in the resulting collection
        Parameters:
        zero - the initial value
        operation - the binary operator applied to the intermediate result and the element
        Returns:
        collection with intermediate results
      • slideBy

        public Iterator<LinkedHashSet<T>> slideBy​(java.util.function.Function<? super T,​?> classifier)
        Description copied from interface: Traversable
        Slides a non-overlapping window of a variable size over this Traversable.

        Each window contains elements with the same class, as determined by classifier. Two consecutive values in this Traversable will be in the same window only if classifier returns equal values for them. Otherwise, the values will constitute the last element of the previous window and the first element of the next window.

        Examples:

        
         [].slideBy(Function.identity()) = []
         [1,2,3,4,4,5].slideBy(Function.identity()) = [[1],[2],[3],[4,4],[5]]
         [1,2,3,10,12,5,7,20,29].slideBy(x -> x/10) = [[1,2,3],[10,12],[5,7],[20,29]]
         
        Specified by:
        slideBy in interface Set<T>
        Specified by:
        slideBy in interface Traversable<T>
        Parameters:
        classifier - A function which classifies elements into classes
        Returns:
        A new Iterator of windows of the grouped elements
      • sliding

        public Iterator<LinkedHashSet<T>> sliding​(int size,
                                                  int step)
        Description copied from interface: Traversable
        Slides a window of a specific size and step size over this Traversable.

        Examples:

         
         [].sliding(1,1) = []
         [1,2,3,4,5].sliding(2,3) = [[1,2],[4,5]]
         [1,2,3,4,5].sliding(2,4) = [[1,2],[5]]
         [1,2,3,4,5].sliding(2,5) = [[1,2]]
         [1,2,3,4].sliding(5,3) = [[1,2,3,4],[4]]
         
         
        Specified by:
        sliding in interface Set<T>
        Specified by:
        sliding in interface Traversable<T>
        Parameters:
        size - a positive window size
        step - a positive step size
        Returns:
        a new Iterator of windows of a specific size using a specific step size
      • span

        public Tuple2<LinkedHashSet<T>,​LinkedHashSet<T>> span​(java.util.function.Predicate<? super T> predicate)
        Description copied from interface: Traversable
        Returns a tuple where the first element is the longest prefix of elements that satisfy the given predicate and the second element is the remainder.
        Specified by:
        span in interface Set<T>
        Specified by:
        span in interface Traversable<T>
        Parameters:
        predicate - A predicate.
        Returns:
        a Tuple containing the longest prefix of elements that satisfy p and the remainder.
      • tail

        public LinkedHashSet<T> tail()
        Description copied from interface: Traversable
        Drops the first element of a non-empty Traversable.
        Specified by:
        tail in interface Set<T>
        Specified by:
        tail in interface Traversable<T>
        Returns:
        A new instance of Traversable containing all elements except the first.
      • tailOption

        public Option<LinkedHashSet<T>> tailOption()
        Description copied from interface: Traversable
        Drops the first element of a non-empty Traversable and returns an Option.
        Specified by:
        tailOption in interface Set<T>
        Specified by:
        tailOption in interface Traversable<T>
        Returns:
        Some(traversable) or None if this is empty.
      • take

        public LinkedHashSet<T> take​(int n)
        Description copied from interface: Traversable
        Takes the first n elements of this or all elements, if this length < n.

        The result is equivalent to sublist(0, max(0, min(length(), n))) but does not throw if n < 0 or n > length().

        In the case of n < 0 the empty instance is returned, in the case of n > length() this is returned.

        Specified by:
        take in interface Set<T>
        Specified by:
        take in interface Traversable<T>
        Parameters:
        n - The number of elements to take.
        Returns:
        A new instance consisting of the first n elements of this or all elements, if this has less than n elements.
      • takeRight

        public LinkedHashSet<T> takeRight​(int n)
        Description copied from interface: Traversable
        Takes the last n elements of this or all elements, if this length < n.

        The result is equivalent to sublist(max(0, min(length(), length() - n)), n), i.e. takeRight will not throw if n < 0 or n > length().

        In the case of n < 0 the empty instance is returned, in the case of n > length() this is returned.

        Specified by:
        takeRight in interface Set<T>
        Specified by:
        takeRight in interface Traversable<T>
        Parameters:
        n - The number of elements to take.
        Returns:
        A new instance consisting of the last n elements of this or all elements, if this has less than n elements.
      • takeUntil

        public LinkedHashSet<T> takeUntil​(java.util.function.Predicate<? super T> predicate)
        Description copied from interface: Traversable
        Takes elements until the predicate holds for the current element.

        Note: This is essentially the same as takeWhile(predicate.negate()). It is intended to be used with method references, which cannot be negated directly.

        Specified by:
        takeUntil in interface Set<T>
        Specified by:
        takeUntil in interface Traversable<T>
        Parameters:
        predicate - A condition tested subsequently for this elements.
        Returns:
        a new instance consisting of all elements before the first one which does satisfy the given predicate.
      • takeWhile

        public LinkedHashSet<T> takeWhile​(java.util.function.Predicate<? super T> predicate)
        Description copied from interface: Traversable
        Takes elements while the predicate holds for the current element.
        Specified by:
        takeWhile in interface Set<T>
        Specified by:
        takeWhile in interface Traversable<T>
        Parameters:
        predicate - A condition tested subsequently for the contained elements.
        Returns:
        a new instance consisting of all elements before the first one which does not satisfy the given predicate.
      • transform

        public <U> U transform​(java.util.function.Function<? super LinkedHashSet<T>,​? extends U> f)
        Transforms this LinkedHashSet.
        Type Parameters:
        U - Type of transformation result
        Parameters:
        f - A transformation
        Returns:
        An instance of type U
        Throws:
        java.lang.NullPointerException - if f is null
      • toJavaSet

        public java.util.LinkedHashSet<T> toJavaSet()
        Description copied from interface: Set
        Converts this Vavr Set to a java.util.Set while preserving characteristics like insertion order (LinkedHashSet) and sort order (SortedSet).
        Specified by:
        toJavaSet in interface Set<T>
        Specified by:
        toJavaSet in interface Value<T>
        Returns:
        a new java.util.Set instance
      • union

        public LinkedHashSet<T> union​(Set<? extends T> elements)
        Adds all of the elements of elements to this set, replacing existing ones if they already present.

        Note that this method has a worst-case quadratic complexity.

        See also addAll(Iterable).

        Specified by:
        union in interface Set<T>
        Parameters:
        elements - The set to form the union with.
        Returns:
        A new set that contains all distinct elements of this and elements set.
      • unzip

        public <T1,​T2> Tuple2<LinkedHashSet<T1>,​LinkedHashSet<T2>> unzip​(java.util.function.Function<? super T,​Tuple2<? extends T1,​? extends T2>> unzipper)
        Description copied from interface: Traversable
        Unzips this elements by mapping this elements to pairs which are subsequently split into two distinct sets.
        Specified by:
        unzip in interface Set<T>
        Specified by:
        unzip in interface Traversable<T>
        Type Parameters:
        T1 - 1st element type of a pair returned by unzipper
        T2 - 2nd element type of a pair returned by unzipper
        Parameters:
        unzipper - a function which converts elements of this to pairs
        Returns:
        A pair of set containing elements split by unzipper
      • unzip3

        public <T1,​T2,​T3> Tuple3<LinkedHashSet<T1>,​LinkedHashSet<T2>,​LinkedHashSet<T3>> unzip3​(java.util.function.Function<? super T,​Tuple3<? extends T1,​? extends T2,​? extends T3>> unzipper)
        Description copied from interface: Traversable
        Unzips this elements by mapping this elements to triples which are subsequently split into three distinct sets.
        Specified by:
        unzip3 in interface Set<T>
        Specified by:
        unzip3 in interface Traversable<T>
        Type Parameters:
        T1 - 1st element type of a triplet returned by unzipper
        T2 - 2nd element type of a triplet returned by unzipper
        T3 - 3rd element type of a triplet returned by unzipper
        Parameters:
        unzipper - a function which converts elements of this to pairs
        Returns:
        A triplet of set containing elements split by unzipper
      • zip

        public <U> LinkedHashSet<Tuple2<T,​U>> zip​(java.lang.Iterable<? extends U> that)
        Description copied from interface: Traversable
        Returns a traversable formed from this traversable and another Iterable collection by combining corresponding elements in pairs. If one of the two iterables is longer than the other, its remaining elements are ignored.

        The length of the returned traversable is the minimum of the lengths of this traversable and that iterable.

        Specified by:
        zip in interface Set<T>
        Specified by:
        zip in interface Traversable<T>
        Type Parameters:
        U - The type of the second half of the returned pairs.
        Parameters:
        that - The Iterable providing the second half of each result pair.
        Returns:
        a new traversable containing pairs consisting of corresponding elements of this traversable and that iterable.
      • zipWith

        public <U,​R> LinkedHashSet<R> zipWith​(java.lang.Iterable<? extends U> that,
                                                    java.util.function.BiFunction<? super T,​? super U,​? extends R> mapper)
        Description copied from interface: Traversable
        Returns a traversable formed from this traversable and another Iterable collection by mapping elements. If one of the two iterables is longer than the other, its remaining elements are ignored.

        The length of the returned traversable is the minimum of the lengths of this traversable and that iterable.

        Specified by:
        zipWith in interface Set<T>
        Specified by:
        zipWith in interface Traversable<T>
        Type Parameters:
        U - The type of the second parameter of the mapper.
        R - The type of the mapped elements.
        Parameters:
        that - The Iterable providing the second parameter of the mapper.
        mapper - a mapper.
        Returns:
        a new traversable containing mapped elements of this traversable and that iterable.
      • zipAll

        public <U> LinkedHashSet<Tuple2<T,​U>> zipAll​(java.lang.Iterable<? extends U> that,
                                                           T thisElem,
                                                           U thatElem)
        Description copied from interface: Traversable
        Returns a traversable formed from this traversable and another Iterable by combining corresponding elements in pairs. If one of the two collections is shorter than the other, placeholder elements are used to extend the shorter collection to the length of the longer.

        The length of the returned traversable is the maximum of the lengths of this traversable and that iterable.

        Special case: if this traversable is shorter than that elements, and that elements contains duplicates, the resulting traversable may be shorter than the maximum of the lengths of this and that because a traversable contains an element at most once.

        If this Traversable is shorter than that, thisElem values are used to fill the result. If that is shorter than this Traversable, thatElem values are used to fill the result.

        Specified by:
        zipAll in interface Set<T>
        Specified by:
        zipAll in interface Traversable<T>
        Type Parameters:
        U - The type of the second half of the returned pairs.
        Parameters:
        that - The Iterable providing the second half of each result pair.
        thisElem - The element to be used to fill up the result if this traversable is shorter than that.
        thatElem - The element to be used to fill up the result if that is shorter than this traversable.
        Returns:
        A new traversable containing pairs consisting of corresponding elements of this traversable and that.
      • zipWithIndex

        public LinkedHashSet<Tuple2<T,​java.lang.Integer>> zipWithIndex()
        Description copied from interface: Traversable
        Zips this traversable with its indices.
        Specified by:
        zipWithIndex in interface Set<T>
        Specified by:
        zipWithIndex in interface Traversable<T>
        Returns:
        A new traversable containing all elements of this traversable paired with their index, starting with 0.
      • zipWithIndex

        public <U> LinkedHashSet<U> zipWithIndex​(java.util.function.BiFunction<? super T,​? super java.lang.Integer,​? extends U> mapper)
        Description copied from interface: Traversable
        Returns a traversable formed from this traversable and another Iterable collection by mapping elements. If one of the two iterables is longer than the other, its remaining elements are ignored.

        The length of the returned traversable is the minimum of the lengths of this traversable and that iterable.

        Specified by:
        zipWithIndex in interface Set<T>
        Specified by:
        zipWithIndex in interface Traversable<T>
        Type Parameters:
        U - The type of the mapped elements.
        Parameters:
        mapper - a mapper.
        Returns:
        a new traversable containing mapped elements of this traversable and that iterable.
      • equals

        public boolean equals​(java.lang.Object o)
        Description copied from interface: Traversable
        In Vavr there are four basic classes of collections:
        • Seq (sequential elements)
        • Set (distinct elements)
        • Map (indexed elements)
        • Multimap (indexed collections)
        Two collection instances of these classes are equal if and only if both collections
        • belong to the same basic collection class (Seq, Set, Map or Multimap)
        • contain the same elements
        • have the same element order, if the collections are of type Seq
        Two Map/Multimap elements, resp. entries, (key1, value1) and (key2, value2) are equal, if the keys are equal and the values are equal.

        Notes:

        • No collection instance equals null, e.g. Queue(1) not equals null.
        • Nulls are allowed and handled as expected, e.g. List(null, 1) equals Stream(null, 1) and HashMap((null, 1)) equals LinkedHashMap((null, 1)).
        • The element order is taken into account for Seq only. E.g. List(null, 1) not equals Stream(1, null) and HashMap((null, 1), ("a", null)) equals LinkedHashMap(("a", null), (null, 1)). The reason is, that we do not know which implementations we compare when having two instances of type Map, Multimap or Set (see Liskov Substitution Principle).
        • Other collection classes are equal if their types are equal and their elements are equal (in iteration order).
        • Iterator equality is defined to be object reference equality.
        Specified by:
        equals in interface Traversable<T>
        Specified by:
        equals in interface Value<T>
        Overrides:
        equals in class java.lang.Object
        Parameters:
        o - an object, may be null
        Returns:
        true, if this collection equals the given object according to the rules described above, false otherwise.
      • hashCode

        public int hashCode()
        Description copied from interface: Traversable
        Returns the hash code of this collection.
        We distinguish between two types of hashes, those for collections with predictable iteration order (like Seq) and those with arbitrary iteration order (like Set, Map and Multimap).
        In all cases the hash of an empty collection is defined to be 1.
        Collections with predictable iteration order are hashed as follows:
        
         int hash = 1;
         for (T t : this) { hash = hash * 31 + Objects.hashCode(t); }
         
        Collections with arbitrary iteration order are hashed in a way such that the hash of a fixed number of elements is independent of their iteration order.
        
         int hash = 1;
         for (T t : this) { hash += Objects.hashCode(t); }
         
        Please note that the particular hashing algorithms may change in a future version of Vavr.
        Generally, hash codes of collections aren't cached in Vavr (opposed to the size/length). Storing hash codes in order to reduce the time complexity would increase the memory footprint. Persistent collections are built upon tree structures, it allows us to implement efficient memory sharing. A drawback of tree structures is that they make it necessary to store collection attributes at each tree node (read: element).
        The computation of the hash code is linear in time, i.e. O(n). If the hash code of a collection is re-calculated often, e.g. when using a List as HashMap key, we might want to cache the hash code. This can be achieved by simply using a wrapper class, which is not included in Vavr but could be implemented like this:
        public final class Hashed<K> {
        
             private final K key;
             private final Lazy<Integer> hashCode;
        
             public Hashed(K key) {
                 this.key = key;
                 this.hashCode = Lazy.of(() -> Objects.hashCode(key));
             }
        
             public K key() {
                 return key;
             }
        
             &#64;Override
             public boolean equals(Object o) {
                 if (o == key) {
                     return true;
                 } else if (key != null && o instanceof Hashed) {
                     final Hashed that = (Hashed) o;
                     return key.equals(that.key);
                 } else {
                     return false;
                 }
             }
        
             &#64;Override
             public int hashCode() {
                 return hashCode.get();
             }
        
             &#64;Override
             public String toString() {
                 return "Hashed(" + (key == null ? "null" : key.toString()) + ")";
             }
         }
        Specified by:
        hashCode in interface Traversable<T>
        Specified by:
        hashCode in interface Value<T>
        Overrides:
        hashCode in class java.lang.Object
        Returns:
        The hash code of this collection
      • stringPrefix

        public java.lang.String stringPrefix()
        Description copied from interface: Value
        Returns the name of this Value type, which is used by toString().
        Specified by:
        stringPrefix in interface Value<T>
        Returns:
        This type name.
      • toString

        public java.lang.String toString()
        Description copied from interface: Value
        Clarifies that values have a proper toString() method implemented.

        See Object.toString().

        Specified by:
        toString in interface Value<T>
        Overrides:
        toString in class java.lang.Object
        Returns:
        A String representation of this object